1. Field of the Invention
The present invention relates generally to the field of construction and, more particularly but without limitation, to the use of pre-stressed concrete members commonly referred to as double-tees.
2. Prior Art
Double-tee structural members are quite often used to form a deck such as, for example, a roof for a building structure. A double-tee generally comprises a planar deck portion, with two legs, or tee portions, extending generally perpendicularly therefrom. Thus, an open space, or cavity, is formed between the legs and a medial portion of the deck, with the deck substantially overhanging the legs. When a plurality of double-tees are positioned side by side and supported on the bearing walls of a building structure, a plurality of such open spaces are formed, as each of the open spaces forms a cavity between one or more of the double-tee members and the wall.
In addition to the bearing walls which support the end portions of the double-tee members, it is frequently the practice to construct walls positioned beneath a deck constructed of double-tees between the ends of the double-tees. Such intermediate walls may be loadbearing or non-loadbearing. In order to isolate or separate a room formed via such a wall, concrete filler panels are supported on top of the walls and positioned to fill the cavities formed via the double-tee members and the walls. These filler panels, constructed to fit snugly within the cavities, are generally rectangularly shaped and normally weigh in excess of one hundred pounds each. Of course, the filler panels can also be utilized in conjunction with the loadbearing walls supporting the end portions of the double-tee members.
Generally, upon initial installation of a typical filler panel, a bead of mortar or caulking compound is run around the joint formed between the filler panel and a respective double-tee member. Thus, by way of a sealed joint, in cooperation with the relatively heavy weight of the filler panel bearing on the wall, it would seem that the filler panel would remain in the desired position. However, due to the well known nature of concrete and steel (the concrete utilized in forming a double-tee member being reinforced with steel), the double-tee member will normally tend to flex upwardly from time to time in relation to the wall. As a result, this flexing may cause the sealed joints to separate. Because of this condition, it is possible for the filler panels to actually fall out of the cavity and off the wall. Clearly, this would present a danger to any person occupying a position near the wall.
In order to alleviate this problem, the manufacturer places steel plates or connecting brackets into the filler panels to be connected to mating steel plates or connecting brackets molded into the double-tee members, so that such connecting brackets can be bolted or welded together when the filler panels are in position. However, this requires the use of more expensive forming methods for molding the double-tee members and filler panels, for each building structure. Clearly, the initial cost of such a solution is more costly; the existing standards to which the double-tee members are constructed have to be changed, resulting in complicating the design of the double-tee members, a change that the huge double-tee construction industry does not like because of the cost alone. Additionally, the cost of assembling each filler panel into place and bolting or welding the connecting brackets is not economical when compared to the present cost of merely sealing the joints with mortar or the like.